Please be careful when adding license tags

When adding LICENSE tags for Free software, please make sure that the
tag is listed in DEFAULT_ACCEPTABLE_LICENSES. (Hopefully this problem
would show up when you do the test build prior to committing anyway :-)
Artistic 2.0 is both Open Source and free and Artistic (1) is only Open
Source (but not declared non-free):
http://www.fsf.org/licensing/licenses/index_html#ArtisticLicensehttp://www.opensource.org/licenses/artistic-license-1.0.php
If the tag isn't in DEFAULT_ACCEPTABLE_LICENSES, please (in the case of
Free-ish software) either add it or instead raise the issue on tech-pkg.
Having LICENSE set to something not in DEFAULT_ACCEPTABLE_LICENSES
breaks automatic builds and updating. (Of course, if the software isn't
free, a broken build is the right answer.)
(This was triggered by running pkg_rolling-replace on a machine that
runs basically only apache/trac/svn/pgsql, and it errored out:
===> Cleaning for p5-DBD-postgresql-2.13.1
ERROR: This package has set PKG_FAIL_REASON:
ERROR: p5-DBD-postgresql-2.13.1 has an unacceptable license: artistic-2.0.
ERROR: To view the license, enter "/usr/bin/make show-license".
ERROR: To indicate acceptance, add this line to /etc/mk.conf:
ERROR: ACCEPTABLE_LICENSES+=artistic-2.0
*** Error code 1
I ran into this with some other package a few days ago.)